Synaptic capture-mediated long-lasting long-term potentiation is strongly dependent on mRNA translation

In the CA1 region of mice hippocampal slices, a strong tetanic stimulation of an input pathway triggers a long-lasting long-term potentiation (L-LTP), which requires protein synthesis for the development of its late phase. A weak tetanic stimulation of one pathway, which is incapable of triggering protein synthesis on its own, can nonetheless induce L-LTP if it is preceded by a strong stimulation of another pathway (synaptic capture-mediated L-LTP). We found that anisomycin (25 microM), a translational inhibitor, impaired the strong stimulation-induced L-LTP more severely when the drug was applied during the whole experiment than when delivered only around the induction period. Taking advantage of this phenomenon, we showed that the synaptic capture-mediated L-LTP was strongly dependent on mRNA translation.